If you want to convert PST to MBOX Thunderbird so you should try eSoftTools PST to MBOX Converter Software. which is a great option. It has a lot of simple, easy, and gentle actions. During the PST to MBOX conversion, email properties are maintained. The software can convert PST to MBOX along with every mailbox item such as - emails, contacts, calendar, attachments, task, notes, and more. All consumers have access to the demo version, which is free to use for all users. You can convert up to 25 email items per folder in the demo version.
Visit here:- Convert PST to Thunderbird
Follow the Steps:
Step 1: Choose the mail source format
Step 2: Select the mailboxes to process
Step 3: Choose the target program or mail format
Step 4: Define the target settings
Step 5: Set the export options
Step 6: Export your email from Thunderbird to Outlook
Step 7: Find your mail in Outlook
Regards,
Peter